DynamicLib.cpp

gistfile1.txt

#include "HelloWorld.h"
#include "DynamicLib.h"

// Extern decl
typedef int32(*rs_trigger)(int32 value);

int32 DynamicLib::thing()
{
  int32 rtn = -1;
  #if PLATFORM_WINDOWS
    FString libpath = TEXT("libextern.dll");
  #elif PLATFORM_MAC
    FString libpath = TEXT("libextern.dylib");
  #elif PLATFORM_LINUX
    FString libpath = TEXT("libextern.so");
  #else
    NOT IMPLEMENTED
  #endif
  FString filePath = FPaths::Combine(*FPaths::GamePluginsDir(), TEXT("libs/"), *libpath);
  UE_LOG(LogTemp, Warning, TEXT("%s"), *filePath);
  if (FPaths::FileExists(filePath))
  {
    UE_LOG(LogTemp, Warning, TEXT("File exists!"));
    void *DLLHandle;
    DLLHandle = FPlatformProcess::GetDllHandle(*filePath); // Retrieve the DLL.
    if (DLLHandle != NULL)
    {
      UE_LOG(LogTemp, Warning, TEXT("Valid lib."));
      FString procName = "rs_trigger";
      rs_trigger fp = NULL;
      fp = (rs_trigger) FPlatformProcess::GetDllExport(DLLHandle, *procName);
      if (fp != NULL) {
        UE_LOG(LogTemp, Warning, TEXT("Valid sym."));
        rtn = (* fp) (100);
        UE_LOG(LogTemp, Warning, TEXT("return: %d"), rtn);
        return rtn;
      }
      else {
        UE_LOG(LogTemp, Warning, TEXT("Invalid sym."));
      }
      FPlatformProcess::FreeDllHandle(DLLHandle);
    }
    else {
      UE_LOG(LogTemp, Warning, TEXT("Invalid lib."));
    }
  }
  else {
    UE_LOG(LogTemp, Warning, TEXT("Invalid file."));
  }
  return -1;
}